Page 62 - MSAM-1-3

Materials Science in Additive Manufacturing Characterization of TPMS structures

compressive load, shear failure occurred at an incline sized dimples, exhibiting a mixed ductile and brittle
angle of approximately 30° between the shear cracking failure mode.
propagation path and the compressive loading
direction (as shown in Figure 13, points 3 – 5). Acknowledgments
(iii) Densification stage. Unfortunately, the samples The authors would like to express their sincere appreciation
slipped and fractured, and thus loading was not to Mr. He Junjie, PhD candidate, from Tokyo University of
continued. Figure 13, point 6, presents the final Agriculture and Technology for his support on the analysis
fractured Schwarz-P structure. Figure 14 shows the of the microstructure.
morphologies of the fracture surface of sample A0.6
after the static compression test. Some partially melted Funding
powder particles are attached to the surface and some None.
unmelted powder particles are locked in the cavities.
The fractured surface consists of a mixture of smooth Conflict of interest
planes and micro-sized dimples, thus exhibiting a
mixed ductile and brittle failure mode. The authors declare that they have no known competing
financial interests or personal relationships that could have
4. Conclusions appeared to influence the work reported in this paper.

In this study, Schwarz-P cellular structures with unit Author contributions
sizes ranging from 1 mm to 5 mm and shape control
factors ranging from 0 to 0.8 obtained using a toolpath- Conceptualization: Shujie Tan, Yicha Zhang
based construction design were fabricated by LPBF using Formal analysis: Ziyu Wang
Ti6Al4V powder. The macrostructure, microstructure, Funding acquisition: Liping Ding
Investigation: Shujie Tan, Xi Zhang
and compression performance of these structures were Methodology: Shujie Tan, Liping Ding, Yicha Zhang
investigated. The main findings are summarized as follows: Project administration: Wenliang Chen
(i) The size of the open pores decreased as the shape Visualization: Xi Zhang
control factor increased and increased as the unit Writing – original draft: Shujie Tan, Xi Zhang
size increased, which is consistent with the designs. Writing – review & editing: Yicha Zhang
However, when the unit size was 1 mm and the shape
control factor was >0.4, the open pores became closed References
cavities, locking in unmelted powder particles. Similar
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Volume 1 Issue 3 (2022) 11 http://doi.org/10.18063/msam.v1i3.17